About
Building the universal
robot runtime.
Making robotics accessible to everyone through open source and open standards.
The Problem
Every robot speaks a different language. Every AI model has a different API. If you want to put a brain in a robot today, you write custom glue code for every combination of hardware and AI. Change the model? Rewrite the integration. Change the robot? Start over.
This fragmentation means that brilliant AI models sit in the cloud doing nothing physical, while capable robot hardware sits on shelves waiting for intelligence. The gap between AI and embodiment is not a technology problem — it's an integration problem.
Our Solution
OpenCastor is the universal adapter. It normalizes every AI provider into a standard interface and maps it to any robot hardware through a single YAML config file. Switch from Apple Foundation Models to Claude with one line. Move from a $50 hobby car to a Dynamixel arm without changing code.
Built on the open RCAN (Robotic Control & Automation Network) specification, OpenCastor configs are portable, validated, and ecosystem-ready. Your robot's definition travels with it.
Origin Story
OpenCastor was created by Craig Merry, inspired by early experiments with the ContinuonAI project exploring the intersection of AI agents and physical robotics. What started as a personal frustration — writing custom glue code for every robot + AI combination — grew into a mission to build the universal adapter layer that the robotics community was missing.
The project evolved from a weekend hack into a serious open-source effort: 166,186 lines of battle-tested Python, 6,404 tests, support for 13+ AI providers including Apple Foundation Models, hardware-accelerated vision via Hailo-8 NPU, and a tiered cognitive architecture that runs a $0 primary brain with optional paid fallbacks. All released under the Apache 2.0 license.
Our Values
🔓 Open by Default
Apache 2.0 license. No feature gates, no premium tiers for core functionality. The runtime is free forever.
🛡️ Safety First
AI hallucinations must never cause physical harm. Hard-coded safety layers, velocity limits, and emergency stops in every loop.
🎯 Simplicity
Five minutes from unbox to agent. If it takes longer, that's a bug. Complexity is the enemy of adoption.
🌐 Universal
Any AI, any hardware, any form factor. If it has a motor and a camera, OpenCastor should be able to drive it.
Journey
The Idea
Frustrated by writing custom integration code for every robot + AI combination. ContinuonAI experiments sparked the vision for a universal adapter layer.
RCAN Spec v0.1
Published the first draft of the Robotic Control & Automation Network specification — a hardware-agnostic YAML schema for robot definition.
OpenCastor v2026.3.8.1
Apple Foundation Models integration, setup UX v2 (stack selection + preflight), 12+ AI providers, Hailo-8 NPU vision, OAK-D depth, tiered brain architecture, 3,431 tests, and a growing community hub. 99,547 lines of Python.
RCAN v1.5 + Fleet UI Launch
Production safety hardening: replay prevention, ESTOP QoS exactly-once delivery, robot identity revocation, consent wire protocol. Protocol 66 conformance reached 94%. Fleet UI launched at app.opencastor.com. Bob↔Alex live robot conversation milestone confirmed end-to-end.
OpenCastor v2026.3.20.3 — RCAN v1.8
Registry Federation Protocol, bandwidth-constrained transports (LoRa/BLE), multi-modal payloads,
Human identity LoA 1/2/3 via FIDO2. All 22 original security/safety audit gaps addressed.
rcan-py v0.6.0 (587 tests), rcan-ts v0.6.0 (405 tests). castor setup wizard with
inline QR codes and fleet-link onboarding. 166,186 lines of code, 6,404 tests.
Growing the Ecosystem
More drivers, more presets, more providers. Partner integrations, community hub expansion, and continued RCAN spec development.
Why "Castor"?
In Greek mythology, Castor and Pollux are the twin stars of the Gemini constellation. Castor — the mortal twin — represents the physical world: robots, hardware, bodies. Pollux — the immortal twin — represents AI: intelligence, reasoning, the cloud.
OpenCastor bridges the mortal and the immortal. It gives physical robots access to digital intelligence.
Links
📦 GitHub
Source code, issues, discussions
🐍 PyPI
pip install opencastor
📄 RCAN Spec
The open robot config standard
💬 Discord
Community chat & support
OpenCastor is open source under the Apache 2.0
License.
Created by Craig Merry.
Join the mission.
OpenCastor is built by the community, for the community. Every contribution matters.